Cabling arrangment, coil apparatus and apparatus for influencing and/or detecting magnetic particles

Abstract

The present invention relates to a cabling arrangement and a coil apparatus for use in an MPI apparatus to increase the sensitivity of the apparatus. The cabling arrangement comprises a first AC terminal ( 320 ), a second AC terminal ( 330 ), wherein said first and second AC terminals are configured for coupling an AC voltage between them, a first internal terminal ( 301 ), a second internal terminal ( 302 ), wherein said first and second internal terminals are configured for coupling a DC voltage between them, a first subset of one or more first conductors ( 401 ) coupled between the first internal terminal and the second AC terminal, and a second subset of one or more second conductors ( 402 ) coupled between the second internal terminal and the second AC terminal, wherein said first and second conductors are arranged to form a coil ( 125, 126, 127; 601, 602, 603, 604 ) to generate a magnetic field in a zone of interest.

1 . A cabling arrangement for generating a magnetic field, comprising:
 a first AC terminal;   a second AC terminal, wherein the first and second AC terminals are arranged to couple an AC voltage between the first AC terminal and the second AC terminal;   a first internal terminal;   a second internal terminal, wherein the first and second internal terminals are arranged to couple a DC voltage between the first internal terminal and the second internal terminal;   a first subset of one or more first conductors, wherein the first subset is coupled between the first internal terminal and the second AC terminal; and   a second subset of one or more second conductors, wherein the second subset is coupled between the second internal terminal and the second AC terminal,   wherein the cabling arrangement enables the superposition of the AC and DC voltages in the first and second conductors,   wherein the said first and second conductors are arranged to form a coil   wherein the coil is arranged to generate a magnetic field in a zone of interest.   
     
     
         2 . The cabling arrangement as claimed in  claim 1 , further comprising coupling elements coupled between the first AC terminal and the first internal terminal and between the first AC terminal and the second internal terminal,
 wherein the said coupling elements comprise:
 at least a first capacitor coupled between the first AC terminal and the first internal terminal, and 
 at least a second capacitor coupled between the first AC terminal and the second internal terminal. 
   
     
     
         3 . The cabling arrangement as claimed in  claim 1 , wherein the first AC terminal is coupled to the first and the second internal terminal. 
     
     
         4 . The cabling arrangement as claimed in  claim 1 , further comprising
 a first capacitive arrangement coupled between the first AC terminal and the first and second internal terminals; and   a second capacitive arrangement coupled between the second AC terminal and the first and second sets of conductors.   
     
     
         5 . The cabling arrangement as claimed in  claim 1 , further comprising:
 a first inductor coupled to the first internal terminal such that the first inductor and the first subset of conductors are located on either side of the first internal terminal; and   a second inductor coupled to the second internal terminal such that the second inductor and the second subset of conductors are located on either side of the second internal terminal,   wherein the cabling arrangement is further configured for coupling the DC voltage to the first inductor and to the second inductor.   
     
     
         6 . The cabling arrangement as claimed in  claim 1 ,
 wherein the first subset comprises two or more first conductors and the second subset comprises two or more second conductors,   wherein the first and second conductors are mechanically arranged substantially in parallel forming a cable,   wherein the cable is wound as a coil.   
     
     
         7 . The cabling arrangement as claimed in  claim 6 , wherein all first conductors are mechanically arranged adjacent to each other and all second conductors are mechanically arranged adjacent to each other. 
     
     
         8 . The cabling arrangement as claimed in  claim 6 , wherein the first conductors and the second conductors are mechanically arranged alternately. 
     
     
         9 . The cabling arrangement as claimed in  claim 6 , further comprising:
 at least a third internal terminal; and   at least three coupling terminals coupled between the first and second subsets and the second AC terminal,   wherein each of first ends of the first conductors of the first subset are coupled to different internal terminals and each of second ends of the first conductors of the first subset are coupled to different coupling terminals,   wherein each of first ends of the second conductors of the second subset are coupled to different internal terminals and each of second ends of the second conductors of the second subset are coupled to different coupling terminals.   
     
     
         10 . The cabling arrangement as claimed in  claim 9 , further comprising:
 a series coupling of one or more capacitors coupled between each internal terminal and the first AC terminal; and/or   a series coupling of one or more capacitors coupled between each coupling terminal and the second AC terminal.   
     
     
         11 . The cabling arrangement as claimed in  claim 1 ,
 wherein the first subset comprises a single first conductor wound as a first coil and the second subset comprises a single second conductor wound as a second coil,   wherein the first coil and the second coil are arranged coaxially.   
     
     
         12 . A coil apparatus, comprising:
 a cabling arrangement as claimed in  claim 1 ; and   a DC voltage or a DC current source coupled between the first and second internal terminals via switches .   
     
     
         13 . An apparatus for influencing and/or detecting magnetic particles in a field of view, which apparatus comprises:
 a selection apparatus comprising:   a selection field signal generator circuit; and   selection field elements;   wherein the selection field generator circuit and the selection field elements are arranged to generate a magnetic selection field,   wherein the magnetic selection field has a pattern in space of its magnetic field strength such that a first sub-zone has a low magnetic field strength where the magnetization of the magnetic particles is not saturated and a second sub-zone has a higher magnetic field strength where the magnetization of the magnetic particles is saturated are formed in the field of view,   a drive apparatus comprising:   
       a drive field signal generator circuit; and 
       drive field, wherein the drive field coils are arranged to change the position in space of the two sub-zones in the field of view using a magnetic drive field, wherein the magnetic field is arranged so that the magnetization of the magnetic material changes locally, and
 one or more coil apparatuses as claimed in  claim 12  forming the drive field coils, wherein the drive field signal generator circuit is coupled to the AC terminals of the one or more cabling arrangements of the one or more coil apparatuses. 
 
     
     
         14 . The apparatus as claimed in  claim 13 , further comprising a drive apparatus and a receiving apparatus, the apparatus comprising:
 the drive field signal generator unit;   a signal receiving unit; and   a drive-receiving coil,   wherein the drive-receiving coil are configured for changing the position in space of the two sub-zones in the field of view by means of a magnetic drive field so that the magnetization of the magnetic material changes locally and for acquiring detection signals,   wherein the detection signals depend on the magnetization in the field of view,   wherein the magnetization is influenced by the change in the position in space of the first and second sub-zone,   wherein the one or more coil apparatuses form the drive-receiving coil.   
     
     
         15 . A method for influencing and/or detecting magnetic particles in a field of view, which method comprises:
 generating a magnetic selection field, the magnetic selection field having a pattern in space of its magnetic field strength such that a first sub-zone has a low magnetic field strength where the magnetization of the magnetic particles is not saturated and a second sub-zone has a higher magnetic field strength where the magnetization of the magnetic particles is saturated are formed in the field of view,   changing the position in space of the two sub-zones in the field of view using a magnetic drive field so that the magnetization of the magnetic material changes locally, and   forming the drive field coils using one or more coil apparatuses as claimed in  claim 12 ,   applying DC currents to drive field coils formed by one or more cabling arrangements as claimed in  claim 1  and used to generate the magnetic drive field, the DC currents being configured to bring magnetic contaminations of the first and second conductors of the one or more cabling arrangements into saturation and to generate no additional static magnetic field or only in the first sub-zone.   
     
     
         16 . The cabling arrangement as claimed in  claim 1 , further comprising:
 a first inductor coupled to the first internal terminal such that the first inductor and the first subset of conductors are located on either side of the first internal terminal;   wherein the cabling arrangement is further configured for coupling the DC voltage to the first inductor and to the second inductor.   
     
     
         17 . The cabling arrangement as claimed in  claim 1 , further comprising:
 a second inductor coupled to the second internal terminal such that the second inductor and the second subset of conductors are located on either side of the second internal terminal,   wherein the cabling arrangement is further configured for coupling the DC voltage to the first inductor and to the second inductor.